Some repair / testing tips to verify this is the part you need:
This is a little more simple to figure out that these parts are an your dryers problem. We will start with belt. If your tub will not turn, but you hear the motor running, your belt has probably come off or is broken. You may also just hear a hum, as if the motor is locked up. This could be the motor, or it could be that the belt has move off of the roller of the 691366 tensioner, and is not able to spin. To get into the dryer simply remove the 2 screws under the lint trap lid, put your knee on the front of the dryer, and pull the top panel towards you while lifting up. Now you will be able to swing the top panel back out of the way. With a 5/16" nut driver, remove the to screws holding the front panel on. You will need a small flat head screwdriver to undo the harness to the door switch to get the panel completely out of the way. Once all of this is done, lift on the front panel and set it aside. Now you can release the tension on the belt, if it's still in one piece, and remove the tub. If your getting squeaking noises during your cycles it could be the 349241 rollers or the 691366 tensioner. Now that you can see your open cabinet you need to manually spin both of your 349241 rollers. If they do not spin freely then you need to replace them. If you don't you are allowing them to create more of a draw on your motor, which could burn it up in time. As for the tensioner the same test applies. Manually spin the 691366 tensioner pulley, if it does not spin freely then replace it. On some of the older Whirlpool dryers and like makes and models they designed the dryer with a tensioner with a glide instead of a roller. If your dryer has a glide on the tensioner replace it and the belt. If your rollers and tensioner are okay, but your belt is dry and cracking you can just buy the 341241 belt itself.
Here is a video on replacing the parts in this kit. It's a gas dryer in the video, but don't worry if you have an electric dryer the only difference in the 2 is the heating parts:
Whirlpool Dryer Repair Kit 4362065
Whirlpool dryer repair kit 4392065 fits Whirlpool and all like makes and models. Kit includes 341241 Belt, 691366 Tensioner, (2) 349241 Rollers. Our cost is $19.00, has a 1 year warranty, and free shipping! Our business hours are Monday - Friday 9 A.M. - 5 P.M., and Saturday 9 A.M. - 12 P.M. eastern standard time. If we can help you in any way during business hours you can give us a call at 260-563-0147. You can also go to our on line form on our contact us page if you on our site after hours and we will get back to you during the next business day.